Field
Embodiments of the present disclosure generally relate to controlling process chambers, and more particularly to techniques for detecting gas leak contamination within a process chamber.
Description of the Related Art
Process chambers used in the production of, for example, semiconductors (e.g., computer processors, coprocessors, solid state storage, and the like) and display devices (e.g., thin film transistor screens, organic light emitting diode screens, and the like) generally establish a vacuum environment in order to deposit various materials on a substrate. Deposition processes, such as physical vapor deposition, may be affected by the presence of a small amount of contaminant gas in the chamber. For example, if an amount of residual gas exceeds a threshold amount, a vapor deposition process may result in depositing excess material on the substrate or depositing too little material on the substrate (both of which are referred to herein as an “out-of-specification substrate”). Both situations may result in wasted wafers or substrates, as an end product resulting from an out-of-specification substrate may not work at all or may exceed an acceptable number of faults.
To determine whether a gas leak is present in a process chamber, which may result in an elevated level of contaminant gases in the chamber, a system operator generally waits for completion of a deposition process on a substrate to test the substrate and determine if the substrate meets a specification for a particular process and/or product. For instance, a gas leak could develop within the chamber during a deposition process. If an amount of material deposited on the substrate falls outside the specification, the system operator can infer that a gas leak was present in the process chamber and attempt to rectify the gas leak. Additionally, gas leaks may develop in a process chamber while the process chamber is idle. When a gas leak develops while the process chamber is idle, a system operator may not detect such a problem until deposition processes are restarted and produced wafers or substrates can be tested against a specification for a particular product. However, such processes result in wasted materials and chamber production time.